Vasculitis is one of the intractable pathological conditions commonly observed in autoimmune diseases, and many cases thereof are refractory to conventionally-used therapeutic methods such as steroids and immunosuppressants and, therefore, new therapeutic methods have been sought. In the vasculitis syndrome, inflammation occurs in arteries of various sizes, and fever, pain in muscles and joints, vascular occlusion, skin ulcer, and mononeuritis multiplex may develop. Vasculitis includes intractable vasculitis syndromes such as polyarteritis nodosa and the aortitis syndrome. Lesions of polyarteritis nodosa are characterized by necrotic inflammations of the media and the adventitia, and aortitis usually develops inflammations of the intima, the media and the adventitia.
Aortitis is also called Takayasu's arteritis. The pathology of vasculitis has been suggested to be associated with IL-6. For example, Noris et al. have reported that blood levels of IL-6 are increased in patients with Takayasu's arteritis in the active stage of pathology compared to normal healthy people (Circulation 1999 Jul. 6; 100 (1); 55-60). However, this paper also reports that the serum concentration of RANTES, one of the kemokines, is also enhanced. Noris et al. also suggest the possibility that these cytokines are responsible for vasculitic lesions in patients with Takayasu's arteritis.